1-Hydrocarbyl-3-mono- and -dithiocarbamoylureas

ABSTRACT

Novel 1-hydrocarbyl-3-(thiocarbamoylthio)ureas and 1-hydrocarbyl-3-(carbamoylthio)ureas are prepared by reacting, in liquid phase, an appropriate isocyanate and S-thiocarbamoylhydrosulfamine or S-carbamoylhydrosulfamine, e.g., S-(dimethylthiocarbamoyl)-N-methylhydrosulfamine or S-(dimethylcarbamoyl)hydrosulfamine. All the compounds are useful as rubber-curing agents.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to, and has as its principal object provision of,novel ureas bearing a thiocarbamoylthio or carbamoylthio substituent.Specifically, these are 1-hydrocarbyl-3-(thiocarbamoylthio) ureas and1-hydrocarbyl-3-(carbamoylthio)ureas, a new class of compounds thatfinds use as rubber curing agents.

2. Prior Art

The novel ureas of this invention have not been described in thechemical literature. The closest art known is that of S. R. Richter inU.S. Pat. No. 3,276,855, which discloses compounds of the type shown bythe formula: ##EQU1##

Japanese Pat. No. 12,246 shows the production of Nacylureaus of thetype: ##EQU2## by reaction of acyl isocyanates with sulfenamides ordiaminosulfides.

F. Kurzer [J. Chem. Soc., London, 549, 3360 (1953)] reports thesynthesis of N-aryl-N'-arylsulfenyl ureas by the following reactions:

ArNHCONH₂ + Ar'SCl → ArNHCONH-S-Ar'

ArNCO + Ar'SNH₂ → ArNHCONH-S-Ar'.

DESCRIPTION OF THE INVENTION

The compounds of this invention are made by liquid-phase reaction of amono- or diisocyanate with an S-thiocarbamoylsulfamine orS-carbamoylsulfamine according to one of the following two equations:##EQU3## The products of the invention may be defined by the followingcomposite formula: ##EQU4##

In the above equations and formulae, the following definitions hold:

Z may be S or O;

R and R¹, alike or different, may be hydrogen or alkyl, cycloalkyl,alkenyl, aryl, alkaryl or aralkyl hydrocarbon of up to 8 carbon atoms;

R² may be alkyl, cycloalkyl, alkenyl, aryl, alkaryl or aralkylhydrocarbon of up to 8 carbon atoms;

R¹ and R², taken together (R¹ + R²), may be (1) a chain of 4, 5 or 6methylene groups, which chain may be substituted with a lower alkylgroup, i.e., an alkyl group of 1 to 4 carbon atoms, or (2) --CH₂ CH₂--O-CH₂ --CH₂ --;

n may be 1 or 2; and

X, When n = 1, may be alkyl of up to 8 carbon atoms; and

X, when n = 2, may be alkylene, O-- or S-interrupted alkylene,alkenylene, alkylenebis(arylene), arylenebis(alkylene), or arylene of upto 13 carbon atoms.

More specifically, R, R¹ and R², alike or different, may be: methyl,ethyl, n- and isopropyl, n-, iso-, sec- and t-butyl, amyl isoamyl,sec-amyl, active amyl, hexyl, 2- and 3-hexyl, 4-methyl-2-pentyl, heptyl,2-, 3- and 4-heptyl, octyl, isooctyl, 3-methylheptyl, 3,3-dimethylhexyl;cyclopentyl, methylcyclopentyl, methylethylcyclopentyl, cyclohexyl,methylcyclohexyl, ethylcyclohexyl, dimethylcyclohexyl, cycloheptyl,cyclooctyl; allyl, α-methallyl, β-methallyl, 2- and 3-butentyl, 2- and3-pentenyl, 2-, 3-, 4- and 5-hexenyl, 3-methyl-3-pentenyl, 6-heptenyl,7-octenyl; phenyl, o-, m- and p-tolyl, o-, m- and p-tolyl, o-, m-andp-ethylphenyl, xylyls, i.e., 2,3-, 2,4-, 2,5-, 2,6-, 3,4- and3,5-dimethylphenyls; benzyl, α- and β-phenylethyl.

Specific radicals within the above definitions of X include, when n = 1,i.e., when derived from a monoisocyanate: methyl, ethyl, propyl, thebutyls, isohexyl, heptyl, octyl and 2-ethylhexyl.

When n = 2, i.e., when X is derived from a diisocyanate, X may be:trimethylene, tetramethylene, 3-methyloctamethylene,3-methoxyheptamethylene, 3-thiapentamethylene, 4-thiaheptamethylene,4-oxaheptamethylene, 2,2-dimethylpentamethylene, decamethylene,dodecamethylene, 3-butoxyhexamethylene, 4,9-dioxadodecamethylene,7-thiatridecamethylene, 1,2-cyclohexylene, 1,4-cyclohexylene;butenylene; methylenebis-p-phenylene, 1,2-ethylene-bis-p-phenylene;4,4'-methoxybiphenylene, 1,5-naphthalene, 4,4'-biphenylene; p-xylylene,p-pheny;enebis(ethyl), 1,4-naphthylenebis(methyl) or1,5-naphthalenebis(methyl).

In the practice of the invention, the mono- or diisocyanate are simplyintimately contacted with the S-thiocarbamoylhydrosulfamine orS-carbamoylhydrosulfamine in liquid phase and the reaction allowed toproceed, usually in solution in a suitable solvent and at around ambienttemperature and pressure.

A large number of isocyanates are known [see, for example, Siefken, Ann.562, 75 (1949)] and many are articles of commerce. Monoisocyanatessuitable for use in the process of the invention include: methyl,propyl, butyl and isohexyl isocyanates.

Diisocyanates include: alkylene and O- or S-interrupted alkylene suchas: trimethylene diisocyanate; tetramethylene diisocyanate;3-methyloctamethylene diisocyanate; 3-methoxyheptamethylenediisocyanate; di(2-isocyanatoethyl)sulfide;di(3-isocyanatopropyl)sulfide; di(3-isocyanatopropyl)oxide;2,2-dimethylpentamethylene diisocyanate; decamethylene diisocyanate;dodecamethylene diisocyanate; 3-butoxyhexamethylene diisocyanate;4,9-dioxadecamethylene diisocyanate; di(6-isocyanatohexyl)sulfide;1,2-di(isocyanatomethyl)cyclohexane;1,4-di(isocyanatomethyl)cyclohexane; alkenylene such as:1,4-diisocyanato-2-butene; alkylenebis(arylene) such as:1,2-ethylene-bis-p-phenylene diisocyanate; arylene such as:3,3'-methoxy-biphenylene-4,4' diisocyanate; 1,5-naphthalenediisocyanate; 4,4'-biphenylene diisocyanate;1,2-ethylene-bis-p-phenylene diisocyanate; and alkylenebis(alkyl) suchas p-xylylene diisocyanate; 1,4-bis(2-isocyanatoethyl)benzene;1,4-bis(isocyanatomethyl)naphthalene;1,5-bis(isocyanatomethyl)naphthalene; and 1,5-tetralin diisocyante.

The S-thiocarbamoylhydrosulfamines ##EQU5## are also a known class ofcompounds and literature references to some of them appear in theexamples. They can be made by the treatment of a dithiocarbamate saltwith a hydroxylamine-O-sulfonate or an N-chloroamine, or by addition ofan oxidizing agent such as sodium hypochlorite or iodine to an aqueousmixture of a dithiocarbamate salt and an amine.

S-Thiocarbamoylhydrosulfamines suitable for the practice of thisinvention are listed in Column C of Table I, following, and may beprepared by reaction of the dithiocarbamate of Column a with the amineof Column B according to the procedure of Smith et al. [J. Org. Chem.14, 935 (1949)].

                                      Table I                                     __________________________________________________________________________           A             B                C                                       __________________________________________________________________________    (CH.sub.3).sub.2 NCS.sub.2 Na                                                                 C.sub.2 H.sub.5 NH.sub.2                                                                 (CH.sub.3).sub.2 NCS.sub.2 --NHC.sub.2                                        H.sub.5                                            (CH.sub.3).sub.2 NCS.sub.2 Na                                                                            (CH.sub.3).sub.2 NCS.sub.2 --NH                    (n-Bu).sub.2 NCS.sub.2 Na                                                                     CH.sub.3 NH.sub.2                                                                        (n-Bu).sub.2 NCS.sub.2 NHCH.sub.3                  (n-Bu)CH.sub.3 NCS.sub.2 Na                                                                   C.sub.3 H.sub.7 NH.sub.2                                                                 (n-Bu)CH.sub.3 NCS.sub.2 NHC.sub.3 H.sub.7         (n-C.sub.3 H.sub.7)CH.sub.3 NCS.sub.2 Na                                                      C.sub.6 H.sub.5 CH.sub.2 NH.sub.2                                                        (n-C.sub.3 H.sub.7)CH.sub.3 NCS.sub.2 NHCH.sub.                               2 C.sub.6 H.sub.5                                  (C.sub.6 H.sub.5 C.sub.2 H.sub.4)CH.sub.3 NCS.sub.2 Na                                        C.sub.6 H.sub.5 NH.sub.2                                                                 (C.sub.6 H.sub.5 C.sub.2 H.sub.4)CH.sub.3                                     NCS.sub.2 NHC.sub.6 H.sub.5                        N(CH.sub.3)CS.sub.2 Na                                                                        p-CH.sub.3 C.sub.6 H.sub.4 NH.sub.2                                                      N(CH.sub.3)CS.sub.2 NH--P-C.sub.6 H.sub.4                                     CH.sub.3                                           CH.sub.3 (CH.sub.2).sub.3 CH(C.sub.2 H.sub.5)CH.sub.2 NCS.sub.                                2,4-(CH.sub.3).sub.2 C.sub.6 H.sub.3 NH.sub.2                                            CH.sub.3 (CH.sub.2).sub.3 CH(C.sub.2 H.sub.5)CH                               .sub.2 NCS.sub.2 NH--2,4-(CH.sub.3).sub.2                                     C.sub.6 H.sub.3                                    (CH.sub.2 =CHCH.sub.2)C.sub.6 H.sub.5 NCS.sub.2 Na                                                       (CH.sub.2 =CHCH.sub.2)C.sub.6 H.sub.5 --NCS.sub                               .2 NH                                              (CH.sub.2 =CCH.sub.3 --CH.sub.2).sub.2 NCS.sub.2 Na                                           n-octyl-NH.sub.2                                                                         (CH.sub.2 =CCH.sub.3 --CH.sub.2).sub.2                                        NCS.sub.2 NH--n-octyl                              (C.sub.6 H.sub.5)--n-C.sub.4 H.sub.9 NCS.sub.2 Na                                             C.sub.6 H.sub.5 --CH.sub.2 CH.sub.2 NH.sub.2                                             (C.sub.6 H.sub.5)--n-C.sub.4 H.sub.9 NCS.sub.2                                NHCH.sub.2 CH.sub.2 C.sub.6 H.sub.5                CH.sub.3 CH=CHCH.sub.2 NHCS.sub.2 Na                                                          C.sub.3 H.sub.7 NH.sub.2                                                                 CH.sub.3 CH=CHCH.sub.2 NHCS.sub.2 NHC.sub.3                                   H.sub.7                                            --CS.sub.2 Na   n-C.sub.6 H.sub.13 NH.sub.2                                                              --CS.sub.2 NH--n-C.sub.6 H.sub.13                  --CS.sub.2 Na   CH.sub.2 =CHCH.sub.2 NH.sub.2                                                            --CS.sub.2 NHCH.sub.2 CH=CH.sub.2                  CS.sub.2 Na     CH.sub.2 =CH(CH.sub.2).sub.4 NH.sub.2                                                    CS.sub.2 NH(CH.sub.2).sub.4 CH=CH.sub.2            N--CS.sub.2 Na  C.sub.2 H.sub.5 NH.sub.2                                                                 --CS.sub.2 NHC.sub.2 H.sub.5                       CH.sub.3 --CS.sub.2 Na                                                                        CH.sub.3 CH=CHCH.sub.2 NH.sub.2                                                          CH.sub.3 --CS.sub.2 NHCH.sub.2 CH=CHCH.sub.3       --CS.sub.2 Na   CH.sub.2 =C(CH.sub.3)CH.sub.2 NH.sub.2                                                   --CS.sub.2 NHCH.sub.2 --C(CH.sub.3)=CH.sub.2       --CS.sub.2 Na   C.sub.6 H.sub.5 NH.sub.2                                                                 --CS.sub.2 NHC.sub.6 H.sub.5                       __________________________________________________________________________

S-Carbamoylhydrosulfamines ##EQU6## usable in the process of theinvention may be made by reaction of thiocarbamate salts with ahydroxylamine-O-sulfonate or an N-chloroamine or by addition of anoxidant such as sodium hypochlorite or iodine to an aqueous mixture of athiocarbamate salt and an amine. They may also be prepared by reactionof amines with chlorocarbonylsulfenyl chloride.

Suitable intermediate S-carbamoylhydrosulfamines are listed in Column Cof Table II, which follows. They may be prepared by oxidation ofmixtures of the thiocarbamate of Column A and the amine of Column b withsodium hypochlorite or iodine as oxidizing agent.

                                      TABLE II                                    __________________________________________________________________________           A               B                     C                                __________________________________________________________________________    (CH.sub.3).sub.2 NCOSNa                                                                      C.sub.6 H.sub.5 NH.sub.2                                                                    (CH.sub.3).sub.2 NCOSNHC.sub.6 H.sub.5           (C.sub.2 H.sub.5).sub.2 NCOSNa                                                               C.sub.6 H.sub.5 CH.sub.2 NH.sub.2                                                           (C.sub.2 H.sub.5).sub.2 NCOSNHCH.sub.2                                        C.sub.6 H.sub.5                                  n-octyl-NHCOSNa                                                                              C.sub.4 H.sub.9 NH.sub.2                                                                    n-octyl-NHCOSNHC.sub.4 H.sub.9                                  CH.sub.3 (CH.sub.2).sub.3 CH(C.sub.2 H.sub.5)CH.sub.2                         NH.sub.2                                                                      CH.sub.3 NH.sub.2                                                             p-CH.sub.3 C.sub.6 H.sub.4 NH.sub.2                            C.sub.6 H.sub.5 N(CH.sub.3)COSNa                                                             C.sub.6 H.sub.5 CH.sub.2 CH.sub.2 NH.sub.2                                                  C.sub.6 H.sub.5 (CH.sub.3)NCOSNHCH.sub.2                                      CH.sub.2 C.sub.6 H.sub.5                         C.sub.6 H.sub.5 NHCOSNa                                                                      CH.sub.2 =CH--CH.sub.2 NH.sub.2                                                             C.sub.6 H.sub.5 NHCOSNHCH.sub.2 --CH=CH.sub.2                                 4                                                [CH.sub.2 =C(CH.sub.3)CH.sub.2 ].sub.2 NCOSNa                                                CH.sub.2 =CH(CH.sub.2).sub.4 NH.sub.2                                                       [CH.sub.2 =C(CH.sub.3)CH.sub.2 ].sub.2                                        NCOSNH(CH.sub. 2).sub.4 CH=CH.sub.2                             C.sub.2 H.sub.5 NH.sub.2                                       (isoamyl).sub.2 NCOSNa                                                                       CH.sub.3 NH.sub.2                                                                           (isoamyl).sub.2 NCOS--NHCH.sub.3                                C.sub.6 H.sub.5 NH.sub.2                                       (CH.sub.2 =CHCH.sub.2)CH.sub.3 NCOSNa                                                        3,4-(CH.sub.3).sub.2 C.sub.6 H.sub.3 NH.sub.2                                               (CH.sub.2 =CH--CH.sub.2)CH.sub.3 NCOS--NH--3,                                 4-(CH.sub.3).sub.2 C.sub.6 H.sub.3               p-CH.sub.3 C.sub.6 H.sub.4 CH.sub.2 (CH.sub.3)NCOSNa                                         (CH.sub.3).sub.2 CH(CH.sub.2).sub.2 NH.sub.2                                                p-CH.sub.3 C.sub.6 H.sub.4 --CH.sub.2                                         (CH.sub.3)NCOS--NH(CH.sub.2).sub.2 CH(CH.sub.                                 3).sub.2                                         (CH.sub.2 =CHCH.sub.2)C.sub.6 H.sub.5 NCOSNa                                                 CH.sub.3 NH.sub.2                                                                           (CH.sub.2 =CHCH.sub.2)C.sub.6 H.sub.5                                         NCOSNHCH.sub.3                                   C.sub.6 H.sub.5 CH.sub.2 NHCOSNa                                                             CH.sub.3 NH.sub.2                                                                           C.sub.6 H.sub.5 CH.sub.2 NH--COSNHCH.sub.3       __________________________________________________________________________

S-Carbamoylhydrosulfamines of the type RNHCOSNHR are similarly useful inthis invention. These may be prepared by the reaction of primary amineswith chlorocarbonylsulfenyl chloride according to the method of Zumachand Kuhle [see Zumach et al., Angew. Chem. Int. Ed. Engl., 9, 57(1970)]. Thus, the amines of Column A of Table III, which follows, yieldthe S-carbamoylhydrosulfamines of Column B by reaction withchlorocarbonylsulfenyl chloride.

                                      TABLE III                                   __________________________________________________________________________    A                       B                                                     __________________________________________________________________________    CH.sub.3 NH.sub.2                                                                         CH.sub.3 NHCOSNHCH.sub.3                                          n-C.sub.3 H.sub.7 NH.sub.2                                                                n-C.sub.3 H.sub.7 NHCOSNH--n-C.sub.3 H.sub.7                      i-C.sub.3 H.sub.7 NH.sub.2                                                                i-C.sub.3 H.sub.7 NHCOSNH--n-C.sub.3 H.sub.7                      C.sub.4 H.sub.9 NH.sub.2                                                                  C.sub.4 H.sub.9 NHCOSNHC.sub.4 H.sub.9                            n-octylNH.sub.2                                                                           n-octylNHCOSNH--n-octyl                                           (CH.sub.3).sub.2 CHCH.sub.2 CH.sub.2 NH.sub.2                                             (CH.sub.3).sub.2 CH(CH.sub.2).sub.2 NHCOSNH(CH.sub.2).sub.2                   CH(CH.sub.3).sub.2                                                CH.sub.2 =CHCH.sub.2 NH.sub.2                                                             CH.sub.2 =CHCH.sub.2 NHCOSNHCH.sub.2 --CH=CH.sub.2                CH.sub.2 =CH(CH.sub.2).sub.4 NH.sub.2                                                     CH.sub.2 =CH(CH.sub.2).sub.4 NHCOSNH(CH.sub.2).sub.4 CH=CH.sub                .2                                                                CH.sub.2 =C(CH.sub.3)CH.sub.2 NH.sub.2                                                    CH.sub.2 =C(CH.sub.3)CH.sub.2 NHCOSNHCH.sub.2 --C(CH.sub.3)=CH                .sub.2                                                            C.sub.6 H.sub.5 NH.sub.2                                                                  C.sub.6 H.sub.5 NHCOSNHC.sub.6 H.sub.5                            o, m, and p-CH.sub.3 C.sub.6 H.sub.4 NH.sub.2                                             o, m and p-CH.sub.3 --C.sub.6 H.sub.4 NHCOSNH--C.sub.6                        H.sub.4 --CH.sub.3                                                2,4-(CH.sub.3).sub.2 C.sub.6 H.sub.3 NH.sub.2                                             2,4-(CH.sub.3).sub.2 C.sub.6 H.sub.3 NHCOSNH--2,4-(CH.sub.3).s                ub.2 C.sub.6 H.sub.3                                              C.sub.6 H.sub.5 CH.sub.2 NH.sub.2                                                         C.sub.6 H.sub.5 CH.sub.2 NHCOSNHCH.sub.2 C.sub.6 H.sub.5          C.sub.6 H.sub.5 CH.sub.2 CH.sub.2 NH.sub.2                                                C.sub.6 H.sub.5 CH.sub.2 CH.sub.2 NHCOSNHCH.sub.2 CH.sub.2                    C.sub.6 H.sub.5                                                   __________________________________________________________________________

Solvents suitable for use in the invention are aliphatic and aromatichydrocarbons such as hexane, isooctane, benzene, toluene, and xylene,and their halogenated derivatives as chloroform, carbon tetrachloride,1,1,1-trichloroethane, trichlorotrifluoroethane, and chlorobenzene,ethers and carbon disulfide. The reactants can also be contacted in meltform if desired. In large-scale preparations, however, the use of aninert solvent is advantageous to aid in control of the reaction.

For most effective utilization of materials, the reactants, are usuallymixed together in molar equivalents, though an amount of the ureaproportional to the reactant used in deficiency will form if thereactants are not used in 1:1 molar ratio.

The reaction is conveniently carried out at temperatures of 10° to100°C., ambient temperature often being employed. Pressure is notcritical, and ambient pressure is usually used for the sake ofconvenience.

The reaction proceeds in the presence or absence of catalysts. Catalystsare advantageous in enabling the use of lower temperatures and/orshorter times. The alkyltin dialkanoates, such as dibutyltin dilaurate,are suitable. Tertiary amines such as trimethylamine, triethylamine,tripropylamine, tetramethylethylenediamine,1,4-diazabicyclo[2.2.2]octane, and pyridine are also effectivecatalysts.

The products are recovered by known means, such as filtration from thereaction solvent as they crystallize out, or by evaporation of thereaction solvent. The products may be purified if desired byrecrystallization from known organic solvents.

EMBODIMENTS OF THE INVENTION

Specific embodiments of the invention are given in the examples whichfollow. Pressures and temperatures are ambient and percentages are byweight unless otherwise noted.

EXAMPLE 1 1-Ethyl-3-(dimethylthiocarbamoylthio)urea ##EQU7##

To 1.36 g. (0.01 mole) of S-(dimethylthiocarbamoyl)hydrosulfamine in 10ml. of carbon tetrachloride was added 0.71 g. (0.01 mole) of ethylisocyanate and 2 drops of dibutyltin dilaurate. After 64 hours, the ureathat formed was filtered off; yield, 1.55 g. (75%). Afterrecrystallization from dioxane, it melted at 173°-175°C.

Anal. Calcd. for C₆ H₁₃ N₃ OS₂ : C, 34.76; H, 6.32; N, 20.27 . Found: C,34.82; H, 6.68; N, 20.14.

EXAMPLE 2 Bis[3-(dimethylthiocarbamoylthio)-p-ureidophenyl[methane##SPC1##

To 5.44 g. (0.04 mole) of S-(dimethylthiocarbamoyl)hydrosulfamine in 35ml. of carbon tetrachloride was added 5 g. (0.02 mole) ofmethylenebis(p-phenyl isocyanate) in 10 ml. of carbon tetrachloride and2 drops of dibutyltin dilaurate. After 24 hours, the separated urea wasfiltered off and washed with dichloromethane; yield, 9.6 g. (92%); m.p.220°C. (dec.).

EXAMPLE 3 1-Methyl-3-(dimethylcarbamoylthio)urea ##EQU8##

One gram (0.017 mole) of methyl isocyanate was added to 2.04 g. ofS-(dimethylcarbamoyl)hydrosulfamine and 1 drop of dibutyltin dilauratedissolved in dichloromethane. After 24 hours the1-methyl-3-(dimethylcarbamoylthio)urea (1.91 g., 64%) was filtered offand recrystallized from dioxane; mp 157°-159°C.

Anal. Calcd. for C₅ H₁₁ N₃ O₂ S: C, 33.89; H, 6.26; N, 23.72. Found: C,34.05; H, 6.35; N, 23.89.

The S-(dimethylcarbamoyl)hydrosulfamine required above was made byaddition of a 30% aqueous solution of sodium hydroxylamine-O-sulfonateto a 30% aqueous solution of potassium dimethylthiocarbamate at15°-20°C. The solution was filtered and extracted six times with ether.After drying with sodium sulfate, the ether was removed to leave a 90 %yield of ##EQU9## mp 63°-64.5°C. after recrystallization from carbontetrachloride.

Anal. Calcd. for C₃ H₈ N₂ OS: C, 29.97; H, 6.71; N, 23.31. Found: C,29.75; H, 6.72; N, 22.87.

EXAMPLE 4 Bis[3-(dimethylcarbamoylthio)-p-ureidophenyl]methane ##SPC2##

Mixing S-(dimethylcarbamoyl)hydrosulfamine and methylenebis(p-phenylisocyanate) in tetrahydrofuran in a mole ratio of 2:1 in the presence ofdibutyltin dilaurate catalyst formed the above bis-urea, mp 280°C.(dec.).

The practice of the invention is further shown by the following TableIV. When the isocyanate of Column A is reacted with the hydrosulfamineof Column B, the 1-hydrocarbyl-3-(thiocarbamoylthio)ureas or1-hydrocarbyl-3-(carbamoylthio)ureas of Column C are obtained.

                                      TABLE IV                                    __________________________________________________________________________           Column A                  Column B                                     __________________________________________________________________________    CH.sub.3 NCO              (CH.sub.3).sub.2 NCSSNH(CH.sub.2).sub.7                                       CH.sub.3                                            ONC(CH.sub.2).sub.6 NCO   [(CH.sub.3).sub.2 CH].sub.2 NCSSNH.sub.2                                  Column C                                                __________________________________________________________________________    ∥                                                                    CH.sub.3 NHCON--S--C--N(CH.sub.3).sub.2                                       |                                                                    (CH.sub.2).sub.7 CH.sub.3                                                     SS                                                                            ∥∥                                                          [(CH.sub.3).sub.2 CH].sub.2 NC--S--NHCONH(CH.sub.2).sub.6 NHCONH--S--C--N[    CH(CH.sub.3).sub.2 ].sub.2                                                    __________________________________________________________________________                              O                                                                             ∥                                                                    C.sub.6 H.sub.5 --NHC--S--NHC.sub.6 H.sub.5                                   O                                                                             ∥                                          OCN--(CH.sub.2).sub.6 --NCO                                                                             C.sub.2 H.sub.5 NHC--S--NHC.sub.2 H.sub.5           OC.sub.6 H.sub.5 C.sub.6 H.sub.5 O                                            ∥|H|∥                                     C.sub.6 H.sub.5 NH-- C--S--N--CO--NHN--CO--N--S--C--NHC.sub.6 H.sub.5         OC.sub.2 H.sub.5 OOC.sub.2 H.sub.5 O                                          ∥|∥HH∥|∥                C.sub.2 H.sub.5 NHC--S--N----C--N--(CH.sub.2).sub.6 --N--C--N--S--CNHC.sub    .2 H.sub.5                                                                    __________________________________________________________________________

UTILITY

The compounds of this invention are useful as rubber curing agents, asillustrated by Example A (wherein parts are by weight).

EXAMPLE A

Part I

Rubber compounding was carried out on a rubber mill as follows:

20 parts of natural rubber

1.2 parts of zinc oxide

0.1 part of stearic acid

0.1 part of mercaptobenzothiazole

1.36 part of product of Example 1

The above ingredients were milled in at 70°C. in the order given and thecompound stock was cured in a mold at 140°C. for 40 minutes. Curedrubber of good elasticity and strength resulted.

Part II

A control run was carried out by repeating the procedure of Part Iexcept that the product of Example 1 was omitted. The product was asticky material with a tensile strength near zero.

Since obvious modifications and equivalents will be evident to thoseskilled in the chemical arts, I propose to be bound only by the appendedclaims.

The embodiments of the invention in which an exclusive property orprivelege is claimed are defined as follows:
 1. A compound of theformula ##EQU10## wherein: Z is S or O;R and R¹, alike or different, arehydrogen, or a hydrocarbon radical of up to 8 carbon atoms selected fromthe group consisting of alkyl, cycloalkyl, alkenyl, aryl, alkaryl, andaralkyl; and R² is a hydrocarbon radical of up to 8 carbon atomsselected from the group consisting of alkyl, cycloalkyl, alkenyl, aryl,alkaryl and aralkyl; or R¹ and R², taken together (R¹ + R²), are (1) achain of 4, 5 or 6 methylene groups which chain may be substituted withan alkyl group of 1 to 4 carbon atoms, or (2) --CH₂ CH₂ --O--CH₂ CH₂ --;and X is a radical of up to 13 carbon atoms selected from the groupconsisting of alkylene, O- or S-interrupted alkylene, alkenylene,alkylenebis(arylene), arylenebis(alkylene), and arylene.
 2. The compoundof claim 1 named bis[3-(dimethylthiocarbamoylthio)-p-ureidophenyl]methane.
 3. The compoundnamed 1-ethyl-3-(dimethylthiocarbamoylthio)urea.
 4. The compound named1-methyl-3-(dimethylcarbamoylthio)urea.